Hacker News: CoryOndrejka

New comment by CoryOndrejka in "St Lucie Nuclear Reactor Unit 1 manually shutdown, 3 control rods drop into core"

CoryOndrejka — Sun, 16 Aug 2026 20:08:09 +0000

[Correction] as noted below, this type of reactor -- unlike US Navy ones -- can remain critical even with dropped rods. So a better statement here would be that the operators would immediately notice a reduction in criticality. thus power and heat. Then it's a process/policy question about shutdown timing.

New comment by CoryOndrejka in "St Lucie Nuclear Reactor Unit 1 manually shutdown, 3 control rods drop into core"

CoryOndrejka — Sun, 16 Aug 2026 20:06:48 +0000

Yup, this is me focusing on US Navy reactors, which is my experience. For them, a rod would already take you sub critical.

New comment by CoryOndrejka in "St Lucie Nuclear Reactor Unit 1 manually shutdown, 3 control rods drop into core"

CoryOndrejka — Sun, 16 Aug 2026 20:05:46 +0000

The dropped rods already shut down the reactor in the sense that it is sub critical. It still has enough leftover heat that it will continue to produce steam for a while, but it would have been almost instantly clear to the operators what had happened.

New comment by CoryOndrejka in "St Lucie Nuclear Reactor Unit 1 manually shutdown, 3 control rods drop into core"

CoryOndrejka — Sun, 16 Aug 2026 20:04:30 +0000

I don't know this plant. In navy submarine reactors like the S5W, you have 440V/3-phase power holding the clamp. If you dropped a rod due to a power or clamp malfunction, usually you'd simply shut down the reactor, drop all the rods and mechanically re-engage the clamp. It could take a few hours which isn't fun because no power which probably means submarine/snorkel depth to run the incredibly noisy diesel, but no step was particularly hard or dangerous.

New comment by CoryOndrejka in "St Lucie Nuclear Reactor Unit 1 manually shutdown, 3 control rods drop into core"

CoryOndrejka — Sun, 16 Aug 2026 18:22:20 +0000

and for the curious who didn't what Chernobyl on HBO, other types of reactors have brief criticality increases on rod insertion, which is somewhere between bad, BAD, and OMFGWTFBBQVERYBAD. In the Chernobyl's case, they entered a criticality region known as "prompt criticality" which is where power doubling can happen at prompt neutron rates (e.g. milliseconds or faster). Very very bad. In the case of pressurized water reactors, this isn't what happens. Every moment of control rod descent is reducing criticality.

New comment by CoryOndrejka in "St Lucie Nuclear Reactor Unit 1 manually shutdown, 3 control rods drop into core"

CoryOndrejka — Sun, 16 Aug 2026 18:17:47 +0000

Exactly what I would have answered :)

New comment by CoryOndrejka in "St Lucie Nuclear Reactor Unit 1 manually shutdown, 3 control rods drop into core"

CoryOndrejka — Sun, 16 Aug 2026 18:17:08 +0000

Of course, but that's not what happened here. For a pressurized water reactor, there are maintenance and procedural questions about why the rod was dropped. People will likely get fired over this. But from a standpoint of reactor and radiological safety, this is largely the design operating correctly and prioritizing radiological containment.

New comment by CoryOndrejka in "St Lucie Nuclear Reactor Unit 1 manually shutdown, 3 control rods drop into core"

CoryOndrejka — Sun, 16 Aug 2026 16:59:07 +0000

Dropped rods are an incident but one that occurs because of pressurized water reactors being very default safe. Controls rods are one way the criticality of a reactor is controlled and US reactors (in general) will go sub critical if even one rod is fully inserted into the core. You will likely have heard of a reactor scram (which goes back to the safety control rod ax man) where in an emergency, all the rods are dropped back into the core, greatly reducing its criticality. In some cases, an interruption of electrical power will cause a rod (or three) to drop accidentally. This is a "dropped rod" incident and will force a reactor shut down because it is now sub critical.

Lots of knock on effects -- sub critical, let heat in the primary loop, less steam and electricity generated in the secondary loop, etc -- but generally a non event that you practice for.

There's no reason this would lead to a radiological event or more significant casualty.

New comment by CoryOndrejka in "We May Be Living Through the Most Consequential Hundred Days in Cyber History"

CoryOndrejka — Mon, 13 Apr 2026 19:09:56 +0000

Combine every attack being a social engineering attack plus foundational model hacking-fu and we're in a shocking interesting place. Identity itself becomes a pretty interesting opportunity/threat. Wrote an oped [1] with friends from Badge on this topic 6 months ago.

[1]: https://idtechwire.com/opinion-in-an-ai-world-every-attack-i...

New comment by CoryOndrejka in "20 years on AWS and never not my job"

CoryOndrejka — Sat, 11 Apr 2026 12:31:37 +0000

> in fact in one of Jeff Barr's AWS user meetups in Second Life

There's so much about that phrase that makes me smile. Easy to forget that Second Life was also one of the earliest users of AWS, S3 first. Jeff Bezos had personally invested in our 2005 round (a round that made Linden Lab a unicorn before that was a thing) and pointed us at Jeff Barr and the work coming from AWS.

In return, Jeff Barr started hosting AWS meetups in Second Life -- this was the era of lots of groups setting up Second Life outposts, from Jonathan Coulton to Reuters.

New comment by CoryOndrejka in "I Built an Open-World Engine for the N64 [video]"

CoryOndrejka — Sun, 29 Mar 2026 21:59:58 +0000

The whole “wheelie to jump cars” but “wheelie require touch on analog stick” is a mechanic I’m shocked other action race games never copied. So much fun to press your luck.

New comment by CoryOndrejka in "I Built an Open-World Engine for the N64 [video]"

CoryOndrejka — Sun, 29 Mar 2026 17:15:31 +0000

According to a sticky note somehow still stuck to RR64 box, the unlcok everything code is (from the main screen): Control Up, Control Up, Left Trigger, Control Down, Z Trigger, Left Trigger, Z Trigger, Control Up

New comment by CoryOndrejka in "I Built an Open-World Engine for the N64 [video]"

CoryOndrejka — Sun, 29 Mar 2026 17:00:23 +0000

Yeah, afaik we all faked it in different ways or decided the almost working setting was good enough.

New comment by CoryOndrejka in "I Built an Open-World Engine for the N64 [video]"

CoryOndrejka — Sun, 29 Mar 2026 16:59:19 +0000

Yeah, so that was what we were in theory "porting." Except that RR3D was streaming off of CD, so they had near infinite disk storage, where we needed to fit in a cartridge. Also -- surprise -- after the contract with EA was signed, it turned out the RR3D team had mostly disbanded inside EA and moved on to other projects, so nobody knew how the streaming worked, where the full map dataset was, how the tracks were represented, etc. Lots of commando visits to EA and long chats later, we had a data dump of the entire map, which was a great start. The compute/storage/graphics performance of the N64 vs PSX were also wildly different, so we ended up having to really rethink virtually all aspects of it.

We also were lucky enough to have an incredible physics engine programmer, so we were running a way better motorcylce simulator than made any kind of sense -- led to huge arguments with our CEO because higher level motorcycles were much harder to ride initially because they were modeled after real performance figures. We fixed that eventually -- Don was right!

Completely agree that none of the games from the CRT era look right on modern TVs. There was a group at GaTech that did some really nice visual simulations of scanline artifacts, but they haven't seemed to generally make it into emulators.

New comment by CoryOndrejka in "I Built an Open-World Engine for the N64 [video]"

CoryOndrejka — Sat, 28 Mar 2026 22:46:39 +0000

We were subleasing from 3Dfx at the time, working on JetMoto, RR64, and Nuke Strike at the same time. It was old school game development — dumb hours, too much coffee, grabbing tubes of Oreos from the 3Dfx micro kitchen, late night In N’ Out runs for animal style and fries well done. Mix of ex-EA, ex-arcade, and all of us thinking how smart we were to not be leaving games to go to Internet startups. Oops.

New comment by CoryOndrejka in "I Built an Open-World Engine for the N64 [video]"

CoryOndrejka — Sat, 28 Mar 2026 22:42:09 +0000

Well, in deeply technical terms, it didn’t work at all and just had like one setting that almost worked. The hardware engineers working on the ASIC tried to slam it in at the last minute and they almost pulled it off. Except the didn’t.

New comment by CoryOndrejka in "I Built an Open-World Engine for the N64 [video]"

CoryOndrejka — Sat, 28 Mar 2026 22:40:15 +0000

The THQ testers figured out you could launch bikes out to the sailboats, too

New comment by CoryOndrejka in "I Built an Open-World Engine for the N64 [video]"

CoryOndrejka — Sat, 28 Mar 2026 22:39:18 +0000

Thank you! We had an absolute blast building it and we just kept playing it. I need to look up the full unlock cheat code.

New comment by CoryOndrejka in "I Built an Open-World Engine for the N64 [video]"

CoryOndrejka — Sat, 28 Mar 2026 22:38:20 +0000

Thank you! I’m cracking up because that’s something we all did while building it, too. It’s part of how the insanity bikes ended up so hilariously overpowered.

New comment by CoryOndrejka in "I Built an Open-World Engine for the N64 [video]"

CoryOndrejka — Sat, 28 Mar 2026 16:46:49 +0000

Very cool. In 1998 (oof) we built Road Rash 64 which was accidentally open world -- even though you had race on a particular road, with a start and finish line, you could drive anywhere, see traffic all over the map, jump off of mountains, etc. The r4k plus reality coprocessor was quite potent -- we got to over 750k shaded triangles per second in optimized testing -- though finicky because you had to manage audio during vblank, etc. Plus, the reality coprocessor fog had a brutal hardware bug that made it really tricky to use.